中国大陆特有华溪蟹属分布格局探讨(甲壳纲,十足目,溪蟹科)

华溪蟹属Sinopotamon是中国淡水蟹类的特有属。在构建种群数据库的基础上,对华溪蟹属的分布格局进行了深入的研究。结果显示:迄今,华溪蟹属已报告75种和9亚种,占中国淡水蟹总数的29.68%(84/283),系中国淡水蟹36个属中所含种及亚种最多的一个类群,广泛分布于赣、鲁、苏、皖、浙、闽、湘、鄂、粤、桂、川、黔、豫、晋、陕、陇、冀计17个省区。华溪蟹属的分布格局与中国自然地理环境区域分异密切相关,自然地理的阻限等因素是导致华溪蟹属在中国高度分化的主要原因,表现出该属下物种对现代自然条件的适应及其遗传与分化至现阶段的结果。依照中国淡水蟹类地理区划的划分,华溪蟹属分属于西南区、华中区、华南区、华北区及其各亚区的东部季风区内,以东洋界物种成分为绝对优势,其地理分布约以24°N为其南限,37°N为北限,经度则为103°E以东直至东南沿海地区。在垂直分布上,该属物种多分布在海拔200～1000m。又以长江中下游一带物种最为丰富,而黄河与淮河流域则相对贫乏。秦岭及其淮河一线成为华溪蟹属东洋界和古北界物种的明显分野地域,但二界之间存在广泛过渡与渗透。据此,华溪蟹属的地理分布,均受制于中国第2级阶梯和第3级阶梯内的秦岭、雪峰山、巫山、太行山、南岭、武夷山等主要山脉及其低岗丘陵与平原地域。

DISTRIBUTION PATTERN OF CHINA MAINLAND-ENDEMIC SINOPOTAMON (CRUSTACEA, DECAPODA, POTAMIDAE)

Sinopotamon is an endemic freshwater crab fauna in China mainland. The distribution pattern of Sinopotamon were detailed studied in this paper, based on building populations database. The results show that, the genera has 84 species (subspecies) (75 species and 9 subspecies) totally until now, about 29.68 % of the total of freshwater crabs in China mainland; Sinopotamon, one of the largest groups of Chinese freshwater crab genus contains 36 genera, distribute widely in 17 provinces including Jiangxi, Hubei, Hunan, Guizhou, Sichuan, Anhui, Zhejiang, Fujian, Guangdong, Henan, Hebei, Guangxi, Jiangsu, Shanxi, Shaanxi, Gansu, Shandong. The distribution of Sinopotamon is closely related to the regionalization of physical geographical environment of China mainland. Physical geography is a major reason which limits the high degree of differentiation of the genera in China mainland. As a result, species are adapt to the current natural conditions, and show its genetic and differentiation in molecular level. According to the division of freshwater crabs geographical sub-region, Sinopotamon, mainly distributing in oriental region, are habitat in Central China, South China, Southwest China and North China, especially in the eastern monsoon region of these various sub-areas. Their geographic distribution range containing the 24°N for South limit, 37°N as northern limit, compared to 103°E longitude until east to the Southeast Coastal Areas. The result also showed that most species of Sinopotamon were found between the elevational range of 200-1 000 m. Sinopotamon is rich in the Northern subtropical (wet type) and in the subtropical (wet type), particularly, the Yangtze River realm is the most abundant of Sinopotamon, otherwise, the area of Yellow River and Huai River is relatively poor. Qinling Mountains and Huai River dive the oriental realm and palaearctic realm Sinopotamon is habitat in, but there was a broad emigration between the two realms. Accordingly, the geographical distribution of Sinopotamon is restricted to geographical obstructs in China mainland, such as Qinling Mountains, Xuefeng Mountain, Wushan, the Taihang Mountains, Nanling, Wuyi Mountains.